The most common method of finishing a wood workpiece is to pass a series of such workpieces at a uniform speed along a transport path past a series of work stations. The workpieces are arrayed with their grain parallel to the transport direction and finished by tools having abrasive surfaces which move in a direction parallel to the transport direction. In this manner the scratches made by even the finest abrasive are hidden in the grain.
Such an arrangement does not, however, function well when the workpiece to be finished is flat and formed with surface hollows or pockets, such as chair seats. In this type of workpiece holidays are left with no finishing, and other spots are sanded to the point where some contours are eliminated.
It is known in this type of machine to guide the individual tools with respective cams so as to cut patterns into the workpiece. Often parts of the shape to be formed must be cut with a tool rotating on one direction while other regions must be cut with a tool that turns in the opposite direction so that splintering is avoided on the edge of a cut. This method of working requires a duplication of finishing tools that is inherently expensive.